Effect of at home and in office bleaching methods on the color-stability of composite resins coated with two different resin-coating agents

Abstract

Background: Due to the effect of teeth whitening on the color and surface properties of composites and the importance of color stability of composite restorations and the effect of glaze materials on surface roughness and since no studies have been performed to evaluate the color stability of glazed composites after teeth bleaching; The aim of this study was to evaluate the color stability of composite resins coated with glaze resins after at home and in office bleaching Materials and Methods: A total of 48 disc-shaped composite specimens (Brazil, Opalis) with dimensions of 2 × 4 mm were prepared which were randomly divided into three groups. The control group did not contain a coating resin, the Bis group coated with LV Biscover glaze resin (Bsco BisCoverTM LV, USA) and the GC group coated with G-COAT PLUS glaze resin (G-COAT PLUS TOKYO, JAPAN). They were divided into two groups, each of which included office bleaching and home bleaching. Color evaluation of the specimens was measured by spectrophotometry (Spectroshade Italy). This measurement was performed at three times immediately after staining process (time 1), immediately after bleaching (time 2) and 2 months after bleaching (time 3). And the color difference between these times was calculated. Results: Repeated two-factor analysis was used to evaluate the effect of glaze type and bleach type on color stability over time. According to the results within and between groups, the effect of time on ΔE values is statistically significant and generally the lowest value is related to ΔE3 (P-value <0.001). The effect of glaze type on the amount of color changes is statistically significant (P-value = 0.021). Bleaching method (at home and in the office) has no significant effect on ΔE (P-value = 0.774). The results show that the interaction of time and type of glaze is statistically significant (P-value = 0.028). According to the results, the interactions of time and method of bleaching (at home and in the office)on, the type of glaze and the method of bleaching (at home and in the office), the time and method of bleaching (at home and in the office) and The type of glaze was not statistically significant (P-value> 0.05). Conclusion: The type of glaze material affected the initial color change and color stability. The bleaching method did not affect the rate of color change and color stability. The initial color change was significant in different groups, but one month after bleaching, color stability was clinically acceptable in all three groups and in both bleaching methods.